Home > Journals > International Angiology > Past Issues > Articles online first > International Angiology 2020 Jun 25

CURRENT ISSUE
 

JOURNAL TOOLS

eTOC
To subscribe
Submit an article
Recommend to your librarian
 

ARTICLE TOOLS

Publication history
Reprints
Permissions
Cite this article as

 

 

International Angiology 2020 Jun 25

DOI: 10.23736/S0392-9590.20.04447-8

Copyright © 2020 EDIZIONI MINERVA MEDICA

language: English

Biomechanical insight of the stent-induced thrombosis following flow-diverting strategy in the management of complicated aortic aneurysms

Yongxue ZHANG 1, 2, Yuan HUANG 3, Zhongzhao TENG 3, Jinguo CUI 2, Qingsheng LU 4 , Zaiping JING 4

1 Department of Surgery, Handan Medical Center of Bethune International Peace Hospital, Handan, China; 2 Department of Interventional Radiology, Bethune International Peace Hospital, Shijiazhuang, China; 3 Department of Radiology, University of Cambridge, Cambridge, UK; 4 Department of Vascular Surgery, Changhai Hospital, Shanghai, China


PDF


BACKGROUND: The flow-diverting stent (FDS) emerges as an alternative strategy in treating complicated aortic aneurysms. However, the biomechanical behavior of the stent-induced thrombus (SIT) remains little understood. This study sought to investigate the impact of SIT on aneurysm wall stress and strain distribution and offer basic evidences for its large-scale application.
METHODS: Aortic aneurysms treated with FDS and followed up over 5 years were selected. Case-specific models were created based on the pre-operative and 12 months follow-up imaging. The aortic central line was generated, perpendicular to which the slice with maximum aneurysm diameter was selected for two-dimensional modeling. Pre- and post-stenting models were compared, with emphasis laid on wall stress distribution and risk factors leading to local stress concentration. Clinical follow-up data was recorded to verify the biomechanical findings.
RESULTS: A total of 6 cases (3 females, average age 56.3±17.2 years) were enrolled in this study. Complete sac thrombosis was documented in 5 cases at 12 months, while residual perfusion was seen in the remaining one. With the formation of SIT, the average wall tensile stress dropped from 58.60±11.11 KPa to 23.56±12.05 KPa (p=0.001) at diastolic phase, and from 88.00±15.94 KPa to 36.02±18.31 KPa (p=0.001) at systolic phase. Intra-wall calcium plaque and irregular, spontaneous intraluminal thrombus were recognized as risk factors for local stress concentration, which could be mitigated by the regular, well-organized SIT. Long-term follow-up at 5 years showed significant aneurysm shrinkage from 57.7±16.2 mm to 51.0±13.7 mm (p=.009).
CONCLUSIONS: The formation of SIT after FDS implantation might protect the aneurysm by reducing the wall tensile stress and erasing the local stress concentration. Clinical follow-up data seems to support the biomechanical role of SIT, but a larger study cohort is needed. A comprehensive understanding of SIT including both biomechanical and biological perspectives are warranted to draw an exhaustive conclusion.


KEY WORDS: Flow-diverting stents; Aorta; Aneurysm; Thrombus; Biomechanics

top of page